Confidential group communication typically depends on the sharing of cryptographic key material among a group of authorized entities. There are a variety of ways in which keys may be shared among multiple entities, however, all such mechanisms depend on a common and reliable understanding of authorization, or group membership. How group membership is established, communicated, updated, and secured from unauthorized tampering are common problems for which a construct is not available that can be effective in the context of dynamic, decentralized, and self-organizing groups.